Device for regulating internalcombustion engines



1945' F. GOSSLAU ET AL 2,382,707

DEVICE FOR REGULATING INTERNAL-COMBUSTION ENGINES Original Filed Oct. 7, 1938 4 Sheets-Sheet 1 1945- F. GOSSLAU ET AL DEVICE FOR REGULATING INTERNAL-COMBUSTION ENGINES Original Filed Oct. 7, 1958 4 Sheets-Sheet 2 Raga/a f/ny k/ay lnvenfors LL mes Sa -4U? Fn'h Gasslau Aqen 1945 F. GOSSLAU ET AL 2,382,707

DEVICE FOR REGULATING INTERNAL-COMBUSTION ENGINES Original Filed Oct. 7, 1938 4 Sheets-Sheet 5 fig. 5

3 4. Coo/er 3: if/brl den/be P aeller I lnvehfors Fri z O S51 1 OLGyn-ggs SLLudt Agent Aug 1945- F. GOSSLAU ET AL DEVICE FOR REGULATING INTERNAL-COMBUSTION ENGINES Original Filed Oct. 7, 1938 4 Shegts-Sheet 4 lnvenfvr s Fritz 60581. AL 301mm 25 Sckh-RH' Werner ZAMMAJK i 0. (9, Agen Patented Aug. 14, 1945 UNITED STATES PATENT OFFICE DEVICE FOR REGULATING INTERNAL- COMBUSTION ENGINES Fritz Gosslau, Berlin-Charlottenburg, Johannes Schmidt,

Berlin Eichkamp,

and Werner Zarnack, Berlin Charlottenburg, Germany; vested in the Alien Property Custodian October 8, 1937 11 Claims.

The present invention relates to a device for regulating internal combustion engines and additional devices, such as, the ignition device, cooling devices, the auxiliary motor for the charging device, adjustable or self regulating propellers, and regulators for controlling the amount of fuel, the regulators being connected to the internal combustion engine and forming a driving unit therewith.

This application is a divisional application based upon certain subject matter contained in our prior copending application Serial No. 233,728, filed October 7, 1938, which has matured into Patent No. 2,297,213, issued September 29, 1942.

The device according to the invention is adapted to serve various purposes.

For instance, the regulation of those devices the optimum position of which changes in accordance with the engine efficiency, is to be automatically effected in dependence on the weight of the air fed in the unit of time.

Accordingly, it is an object of'the invention to provide for an automatic regulation in dependence on the Weight of the air fed in the unit of time of such devices that are automatically adjusted to their optimum position in accordance with the engine efficiency.

A further object of the invention is to provide a device which allows a particularly favorable utilization of the fuel reserve of the engine. A regulating device of this type has, for instance, the advantage that aircraft provided with such regulators have a range of flight which is greater than with the use of the hitherto known regulating devices.

A still further object of the invention is to provide a regulating device which operates under all service conditions free of objection and this also, as is required for instance at aircraft arts, in a very great height above the earth.

Another object of the invention is to provide a device which seldom or never requires operation of the pilot.

The regulating device according to the invention, moreover, is adapted also for use in aircraft provided with variable pitch propellers.

Furthermore, the regulating device maybe so constructed that the various regulating actions aimed at may be obtained independent of the state of the air.

The hitherto known means for regulating internal combustion engines and additional devices connected thereto generally are satisfactory only for some of the above mentioned requirements.

tloned requirements may be fulfilled in a very simple manner by providing a device which operates in dependence on the weight of the air fed in a unit of time during charging and which controls the internal combustion engine as well as any number of additional devices in dependence on the weight of air fed in a unit of time.

The regulator according to the invention may be connected to the ignition device of the internal combustion engine for controlling the time of ignition. It is also feasible to connect the regulator to the cooling apparatus of that internal combustion engine for controlling the amount of cooling medium, or to the adjusting members of an adjustable or self regulating propeller coupled to the internal combustion engin for adjusting the pitch of the propeller blades.

A preferred use of the regulating device consists in connecting the measuring instrument operating in dependence on the weight of the air supplied in a unit of time to regulating means influence the quantity of fuel fed in a unit of time.

Eventually, the same regulator may simultaneously control the feed of the fuel and the drive of an auxiliary motor for the charging device, of coolers, ignition devices, adjustable propellers clutched to the engine and so on.

We have, furthermore, found, that for carrying into effect the general inventive idea consisting in utilizing the weight of the air drawn in and dealt with in a unit of time for regulating the various devices it is preferable to start from the following mathematical-physical relation:

wherein G is the weight of the air, C is a dimension constant, Ap is the difference of certain pressures of the air in the suction pipe and v is the state of the air, i. e. its specific volume, at one of the points of the pressure differences.

It is also possible to start from the following relation:

wherein G is the weight of the air, C is a dimension constant, p is the pressure of the air, R is the gas constant, T is the absolute temperature, and Age is the air pressure difference referred to above.

If the regulator is to operate according to the last mentioned mathematical relation, it is recommendable for producing the pressure differences to Now, we have found that all the above menuseapartially restricted tube, for instance aVen- The as P preferably is measured with the aid of a vacuum diaphragm bellows arranged in the air current and is then converted into corresponding control movements.

Instead of the Venturi tube any other wellknown measuring instrument may be used. However, Venturi tubes have the advantage that practically no throttle losses occur.

For carrying into effect the above mentioned mathematical-physical relations preferably curve discs, cams or the like are provided, the control surfaces of which are formed according to a logarithmic and a number value law respectively. By means of such curve discs or cams, the values of the quotient may be converted into values of the sum and into values of differences, respectively, so that for instance auxiliary devices provided with balance beams may be used upon the arms of which act the pressures to be superimposed.

Further features and capabilities of the present invention will be apparent from -the following description of the various modifications taken in connection with the drawings.

Various modifications are diagrammatically illustrated by way of example only in the drawings, wherein:

Fig. l is a diagrammatic representation of a construction of a regulator for controlling the fuel p y p p,

Fig. 2 is a diagram relating to the regulation,

Fig. 3 is a diagrammatic repersentation of a detail of the construction of Fig. 1 wherein a gate is provided for adjusting the arrangement to the use of different fuels,

Fig. 4 is a diagrammatic representation of a portion of a regulator construction in which a centrifugal regulator serving as an additional regulating element is positively driven by the internal combustion engine,

Fig. 5 is an elevation of an internal combustion engine coupled to a propeller having adjustable blades,

Figs. 6, '7 and 8 are a plan view, a side elevation and a front elevation, respectively, of details of a special coupling device for the regulator of Figs. 4 and 5, and

Fig. 9 is a diagrammatic representation of a regulator arrangement particularly adapted for regulating the ignition of an aircraft engine, the position of the flaps of the aircraft controlling the fiow of cooling air, the pitch of the propeller and the like.

In one of the embodiments shown in the drawings the measuring instrument serving as an actuator for the fuel regulation is designed and arranged to respond to the weight of air temporarily fed into the internal combustion engine. Ac-

cordingly, the pilot is completely relieved, and

used which is inserted in the suction pipe or air intake leading to the internal combustion engine.

For measuring the state of the air, i. e., its speciflc volume, preferably a diaphragm chamber containing air or a barometer or thermo-barometer operating on the same principle may be used.

When using the above mentioned measuring devices as actuator for the associated power converting members, which may be hydraulic pistons or the like, logarithmic curve discs form the return drive for the actuators. When such logarithmic curve discs are used, the power pistons move in accordance with the logarithm values of the cams.

The control members connected to the two measuring devices, which may be a Venturi tube and a bellows preferably are connected to a common balance beam or the like linkage which by way of a further curve disc.acts upon the fuel regulator. Furthermore, a device may also be provided which may be actuated automatically or by hand and which allows adjustment of grade set-tings for the various operative conditions, as for instance half load, full load, overload, or for a'definite number of revolutions of the engine. The adjusting device may substantially consist of a toggle lever system.

The embodiment of the invention shown in Fig. 1 further serves to solve the following problem.

In connection with the known single lever devices for adjusting aircraft engines it is usual to provide a position of the lever for cruising load corresponding to 80% of the full load at which the motor is driven with an excess of air, i. e. with a poor or weak mixture. Another position is provided for a 100% output, at which the motor operates with a very rich mixture. This arrangement is disadvantageous, because, if the aircraft is flying in great height and the engine, there- 40 fore, due to insufficient charging pressure, has

% of its full efliciency or output only, and also in still greater heights the pilot must adjust the lever to the position corresponding to output. Therefore in great heights the aircraft can only be driven with a rich mixture, notwithstanding the fact, that in such heights an aircraft engine during a long flight'even with the greatest charging pressure could substantially more economically be driven with a poor mixture.

To obviate these drawbacks the device according to the invention is so constructed that as long as the quantity of air drawn in and therefore the engine output or efficiency remains below a predetermined value of the full output, a poor mixture and with increasing output a gradually richer mixture is supplied. The formation of the mixture, therefore, is according to the invention no longer dependent on the position of the efliciency lever, but on the quantity of fuel mixture consumed by the engine. In this manner the pilot may choose any desired charging pressure in a height in which the engine at the very best draws in 80% of the total quantity of air only. The pilot will fly in any case with a poor or weak mixture. To allow the pilot to set a richer mixture in special cases, for instance when fighting, a second lever may be provided in the linkage for influencing the formation of the mixture, or the efiiciency lever may be brought into a position in which it allows supply of aricher mixture.

In the embodiment shown in Fig. 1 one cylinder I of the motor or any other internal combustion engines only is represented. The engine is preferably an aircraft motor. Piston 2 is moved up and down in cylinder l and is connected by means of piston rod 8 to crank 4 of crank shaft 5. Cylinder I is provided with outlet valve 6 connected to a pipe leading to exhaust 1. Inlet valve 8 is provided in cylinder I. Gear wheel 9 is mounted on shaft and engages gear wheel H) on shaft Shaft carries rotor l2 of a centrifugal blower serving as charging device. Fixed casing |3 ofthe charger is connected by way of pipe l4 to inlet valve 8 and serves to supply combustion air under pressure. Spray nozzle l5 for the fuel extends into pipe l4. Nozzle I5 is connected to fuel pump I6 constructed as a geared pump, the construction of which is well known and therefore need not be described. The quantity of fuel fed by pump I6 is regulated by lever |1 acting upon a well known control valve of the pump not shown in the drawings.

Air flows into centrifugal blower l2, l3 by means of Venturi tube l8 open to the outer relative air current and having a narrow discharge end l9. Venturi tube l8 flares like a difiusor towards the charger up to the width of inlet socket 20. Tappin points 2| and 22 are provided at the smallest and at the widest part respectively of Venturi tube l8. Tapping 22 is con nected by way of pipe 23 with the interior space 24 of chamber 25. Diaphragm box 26 formed by a corrugated tube is arranged in the interior space 24 and closed against the outer atmosphere. The interior of diaphraggm box 26 is by means of pipe 21 connected to tapping 2|. The difference of pressure occurring at the two tapping points 2| and 22 of Venturi tube I8 due to the flow of air causes expansion and contraction respectively of diaphragm box 26. Rod 28 is rigidly connected to diaphragm box 26 and is actuated by the contraction and expansion movements of diaphragm box 26. Two pistons 26, 38 are mounted on rod 28 and are shiftably arranged in sleeve 3| which in turn is movably arranged in cylinder 32. Spring 33 tends to press sleeve 3| upwardly. Inlet pipe 33 and two outlet pipes 34, 35 for pressure oil are connected to cylinder 32. Cylinder 32 is furthermore connected by way of channels 36, 31 to chambers 38, 38 which are arranged above and below piston 40 repectively. Piston 29 and piston 30 effeet in a well-known manner the supply and the discharge of pressure oil into and out of the chambers 38 and 39 respectively, whereby piston 48 is moved upwardly or downwardly. Besides from the position of pistons 29, 30 the admission and discharge of the pressure oil also depends on the position of sleeve 3| and on the position of the openings provided in sleeve 3|. Piston rod 4| carrying cam 42 is connected to piston 48. Cam 42 is in the form of a logarithmic curve. Roller 43 bearing against cam 42 is provided at one arm 44 of a bell-crank pivotally mounted on bolt 45. The end of the other arm 46 of this bell-crank is fork-shaped and engages pin 41 provided at rod 48 rigidly connected to sleeve 3|. In this manner piston 40 controls sleeve 3| in a logarithmic ratio according to the pressure difference of tapping point 2|, 22. Spring 33 tends to always press roller 43 against curve 42.

The lower end of rod 4| carries pin 49 engaging fork 50 of balance beam 5| and acting upon the latter. Upon the other arm of balance beam 5|, also having fork-shaped end portions 52, acts piston rod 53 controlled by piston 54. Piston rod 53 also carries curve'55 in the formof a logarithmic curve which, however, ex-

tends in the reverse direction with regard to curve 42. Against curve 55 bears by means of roller 56 the one arm 51 of a bell-crank pivoted on bolt 58. The other fork-shaped arm 59 of the bell-crank engages pin 68 of rod 62 rigidly connected to sleeve 6|. Sleeve 6| is shiftably arranged in cylinder 64 against the action of spring 63. Cylinder 64 is provided with inlet pipe 65 and two outlet pipes 66, 61 carrying pressure oil. On the other side of cylinder 64 channels 68, 69 are provided which in accordance with the position of sleeve 6| and of pistons 18 and 1| slidably arranged in sleeve 6| effect the admission and discharge of pressure oil into and out of chambers 12, 13 arranged above and below piston 54, respectively. Pistons 18, 1| are fixed to piston rod 14 connected to diaphragm box 15 formed by a corrugated tube. Piston rod 14 is controlled by the expansion and contraction movements of box 15. Box 15 is closed against the outer atmosphere and contains a definite weight of air, whereas atmospheric pressure prevails in space 16 of chamber 11, surrounding diaphragm box 15, so that expansion and contraction of box 15 occurs in dependence on the state of air prevailing at a given time.

Rod 39 is linked to the center 18 of balance beam 5|. Since piston 48 due to the control of sleeve 3| transfers to balance beam 5| the loga rithm value of the pressure difference at the two measuring points 2|, 22 while piston 54 transfers to balance beam 5| the negative logarithm value of the state of the air, a displacement of rod 19 results corresponding to half the difference of the logarithm value of the pressure difference and the logarithm value of the state of the air. Rod 19 carries another push curve which introduces into the calculation the constants and the number value of the above mentioned formula. I

Curve 80 is, moreover, so formed that, as long as the amount of aid drawn in and, therefore, the engine output remains below a predetermined value, for instance 80% of the full load, a poor mixture is supplied, whereas at a higher output a mixture gradually becoming richer is supplied. Against curve 80 bears by means of roller 8| the one arm 82 of a bell-crank pivoted at 83, the other arm 84 of the bell-crank being connected to toggle lever. The toggle lever consists of two links 85, 86. Lever 88 is connected at the connecting point of links 86, 86 and may effect diiferent positions of toggle lever 85, 86. The free end of link 86 is connected to lever I1, and thereby influences as described above the quantity of fuel delivered by fuel pump I6. Lever 88 may be actuated by a pilot. This either is effected by connecting lever 88 to an emergency lever which is pulled by the pilot in special cases, for instance during fighting, only to allow an enrichment of the mixture in great heights also. Or else by connecting lever 88 to the ef- -ficiency lever so that by shifting the latter into the position the toggle lever linkage is infiuenced and thereby an enrichment of the fuel mixture is effected.

The automatic regulation of the adjustment to a poor and rich mixture, respectively, independence on the mixture dealt with in the engine is effected by the shape of cam 80, whereas the additional arbitrary control of the mixture is effected by lever 88.

In connection with the above mentioned devices for regulating the fuel supply in dependence Whereas the accessory value a has quite an unimportant influence on the measuring exactness of the Venturi tube and quickly approaches a constant value with increasing height of flight, the indication by the accessory expansion value c of the Venturi tube is disturbed in an increasing degree with increasing height of flight. It has been ascertained by tests, that between 0 and kilometers of height the value of e for a definite weight of air was reduced for about 3.5%.

To compensate this defect, th'e influence of the variable value of e is according to the invention taken into consideration. For this purpose preferably the regulator which is controlled by the alteration of the specific weight of the air is used. This correction is effected by superimposing the control curve of return sleeve 6| of the regulator by the curve for the variable value c Hereby the amplitude of the regulator depending upon the specific volume of the. air increases with increasing height not only in proportion to the increase of the specific volume of the air, but additionally in proportion to the alteration of the value c,

An example of this modified construction according to the invention is shown in Fig. 1 in connection with Fig. 2 which graphically represents the curve of the value of e mentioned above and of the logarithm of v in dependence of the way of regulation.

In this modified regulator construction piston rod 53 carries a curve 55 which according to Fig. 2 consists of a logarithmic curve corresponding to the expansion characteristic of the box 15, whereby a curve, shaped in accordance with the alteration of the expansion accessory value c is superimposed to this characteristic. Here curve 55 also extends in the reverse direction with regard to curve 42.

Since piston 48 due to the control of sleeve 3| transfers to balance beam 5| the logarithm value of the pressure difference prevailing at the two tapping points 2i, 22,- while piston 54 transfers to balance beam 5| the negative logarithm Value of the state of air under consideration of the value 2, rod I9 is displaced so that this displacement corresponds to half the difference of the logarithm value of the pressure difference and of the logarithm valueof the pressuredifierence and of the logarithm value of the state of the air under consideration of the value c.

Lever 88 again may be actuated by the pilot. This is effected either by connecting lever 88 to an emergency lever which is pulled by the pilot in special cases, for instance during fighting, only to allow an enrichment of the mixture in greater heights also. Or else lever 88 may be connected to the efflciency lever in such a manner that the shifting of the efliciency lever into the 110% position influences the toggle lever linkage and thereby enriches the fuel mixture.

The value c depends besides of the height of flight on the load of the motor also. The modification shown and described neglects the alteration which per se is required when the motor load changes. Strictly speaking, therefore, this modification is correct for a definite motor output only. Practically, however, an additional correction in accordance with changes of the motor output, may be obviated, since the correction made is not very great itself and, moreover, is of importance within the limited ranges of the motor output during cruising speed only. If a complicated additional regulation in accordance with the motor output is to be prevented, it may evidently be included in the bargain that certain deviations occur at full load and when the motor runs idle.

Another modification of the present regulator I has the advantage, that it may be used for the most different fuels and may very quickly be regulated to the quantity of air required for the particular fuel used. For this purpose, a device for arbitrarily adjusting the quantity of fuel to be supplied is provided in connection with the automatic regulator,

Preferably, this device consists therein that the length of one or more of the lever arms of the regulator linkage is adjustable, one lever of the linkage being provided with a gate in which the pivot point of another lever is arbitrarily shiftable and fixable in any desired position. The arbitrarily adjustable portion of the regulator prefarably is connected to an indicating device which indicates on a scale that quantity of fuel which corresponds to the optimum mixing ratio of the fuel in question.

For this device, the construction shown in Fig. 1 may advantageously be used in which between bell-crank 82, 84 on the one hand and fuel pump I8, I! on the other hand an adjustable device, for instance a device as shown in Fig. 3, is inserted. Otherwise the construction of the regulator may be exactly the same as the one shown in Fig. 1.

Rod I9 carries push curve 80 against which bears by means of roller 8| lever arm 82 pivotally arranged at 83. The other lever arm 84 of this bell-crank acts upon link I85. The other end of link I85 is provided with pin I88 which engages gate I81 in which it may be arbitrarily adjusted and fixed in any desired position. Gate I8! is carried by lever I88 linked to the casing at I88.

' The other end I98 of lever I88 acts upon lever I1,

whereby the quantity of fuel injected by fuel pump I6 is regulated in a well-known manner.

Scale I9I is provided adjacent gate I81. Scale I9I bears the marks for the most favorable adjustment of the air-fuel mixture for different kinds of fuel. So for instance, a mark may be provided for each kind of fuel. Therefore, when changing from one fuel to another it is only necessary to adjust the pivot point I88 of link I in gate I81 to that mark which designates the fuel now to be used. Then the motor is at once adapted and without the necessity to effect further time-consuming regulations to operate with the new fuel under the most favorable conditions with regard to the fuel-air mixture.

In a further modified construction the measuring of the weight of the air drawn in and dealt with in the engine in a unit of time is utilized for influencing certain regulator members. This construction is particularly adapted for aircraft engines used to drive propellers and represents the followng improvement.

In known devices of this type a definite position of a switch lever is provided for each weight of air, and the quantity of fuel supplied depends on the position of the switch lever. Frequently the pressure of a pump for injecting fuel, for instance into the mixing chamber, is influenced by the regulator. The regulator then correctly operates as long as the fuel pump driven by the engine maintains constant the injection pressure chosen independent of the prevailing engine speed.

Supposing a regulator wherein the weight of air measured in each unit of time is utilized as impulse cooperates with a pump feeding the fuel in dependence of the engine speed and provided with a regulator for .the fuel fed, the regulator being provided with an adjustable regulator member and the pump feeding a definite quantity of fuel determined by the number of revolutions of the engine and the setting of the regulator member; Very unfavorable operating conditions result in this case if an aircraft is to be driven by an engine having different numbers of revolutions with an equal output, i. e. with an equal weight of air.

Such conditions prevail if an aircraft provided with a socalled non-adjustable propeller changes from horizontal flight to climbing. When climbing, the number of revolutions of the engine decreases with regard to the number of revolutions of the engine during horizontal flight. This is due to the low pitch of the propeller. Hereby the feed of the pump is reduced for the same position of the regulator rod so that the correct mixing ratio for the horizontal flight becomes too poor for climbing.

The reverse proportionsfor instance occur, if the aircraft is pushed or falls. Generally speaking, an undesired change of the mixing ratio occurs with each change of the velocity of the aircraft and with an equal motor output. This is due to the fact that the mixture regulator acts according to a certain time (hourly weight of air), the pump, however, acts on the individual cycle of operation.

The above described dimculties are obviated according to the invention in a simple manner by providing a special regulator. This special regulator is driven in dependence of the number of revolutions of the engine and influences the actual values of the regulation effected by the regulator responding to the quantity of air dealt with in a unit of time so that at all operating conditions the corresponding calculated mixing ratio of air and fuel is warranted. For instance a centrifugal regulator driven by the internal combustion engine is connected by way of its control member to the regulator for the fuel fed by the pump and influenced by the air dealt with in the engine in such a manner that it influences a valve member controlled by this regulator and provided in the fuel pipe.

According to the invention such a device is so constructed that the regulating value of the meter for the air fed into the engine may be corrected in dependence of the engine speed.

.According. to another modification of the present invention the regulator influenced in dependence of the number of revolutions of the en- 7 gine is formed as a regulator for the adjustable propeller. the shaft of which is positively coupled to the drive shaft of the pump feeding the fuel. This regulator automatically adjusts itself to a constant number of revolutions in a manner known per se. The special advantage of this construction consists therein that with the use of adjustable propellers provided with regulators forthe number of revolutions, it is not necessary to provide a special regulator which for instance corresponding t the construction previously described acts on the control rod for the fuel pump. With this last described construction with adjustable propeller the regulator provided for the p opeller effects the regulation of the fuel feed aimed at. The fuel pump needs to be regulated according to the temporary quantity only of the consumed air since the number of revolutions of the pump is perfectly constant.

A further-modification of the present invention is particularly adapted for aircraft engines with adjustable propellers operating in two spaced ranges. When using such adjustable propellers the dimculty may occur similar to that arising in connection wtih fixed propellers, i. e. that the mixing ratio always will be richer at the higher number of revolutions of the engine than at the lower number of revolutions. This difficulty may according to the invention be overcome by the fact that the regulator, influenced in dependence on the number of revolutions, is arranged as a regulator for the propeller automatically setting to a plurality of constant number of revolutions. Furthermore, control means, for instance correspondingly shaped curve discs, are provided which on setting a range of higher number of revolutions simultaneously and automatically effect an enrichment of the mixture of fuel and air. For example, the second range of number of revolutions of the propeller is chosen so much higher than the first range that the change of the number of revolutions just results in an enrichment from the cruising mixture to the heavy duty mixture. This construction of the regulating device also is characterized by a particularly great simplicity.

When constructing and using the last described device, the regulator is once set to a definite mixing ratio as poor as possible and determined for cruising speed. At the lower number of revolutions this mixing ratio then remains constant at each position of the so-called pilot lever as far as to the 100% position. Only if the propeller is switched to the higher number of revolutions an enrichment also is positively effected so that the engine operates with highest emciency.

Preferably, the switch lever for the propeller is positively coupled to the pilot lever in such a manner that, on shifting the pilot lever from the position to the position, the propeller also is adjusted to the higher number of revolutions, This modification of the device has the special advantage that by means of a single lever the enrichment as well as the increase of the number of revolutions may be effected. As for the two ranges of operation two ignition points only are required. The device may be improved further by also coupling the switching gear of the ignition device, preferably in the same manner, to the above described multiple switching lever.

Preferably, the various levers are rotatably mounted upon a common shaft and are movabiy arranged in a common gate provided for engaging and disengaging the levers.

With the present device provided with a regulator for the fuel fed by the fuel pump which may be influenced by pressure differences prevailing in an air measuring device actuated by the engine, the regulator is coupled to an auxiliary regulator. This auxiliary regulator is influenced by alterations of the state of the outer atmosphere, for instance on account of different heights above the earth and correspondingly controls so that the regulating movements of the first regulator are compensated.

As an example of the last described regulating device the construction described in connection with Fig. 1 may again be used, certain regulating members and devices being constructed nd arranged in accordance with Fig. 4.

Spraying nozzle 2|! is not provided in the air suction pipe leading to the cylinder, but in the cylinder cover. Supply pipe 2|6 for the fuel is connected to nozzle 2|5. The other end of pip 2|6 is connected to the outlet socket of feed pump 29! which may be a geared pump.

By means of roller 28| lever arm 282 of a bellcrank pivoted on bolt 283 bears against curve 288. The other arm 284 of the bell-crank is fixed to a toggle lever consisting of two links 285, 286. Lever 28! acts as the connecting point of link 285, 286. Axiallydisplaceable member 288 for instance a sleeve, is arranged on lever 281.

Two weights 284, 295 of a centrifugal regulator bear against member 288. Spring 290 tending to move sleeve 288 downwardly bears against rod 289 fixed to sleeve 288 and displaceable axially with sleeve 288. Spring 298 bears with its other end against link 29| on which two arms 292, 293 are pivoted carrying weights 294 and 295, respectively.

As may be seen from Fig. 4, weights 294, 295 of the centrifugal governor 28], 295 driven by the internal combustion engine |-5 are swung outwardly at higher number of revolutions of the engine so that sleeve 288 is drawn upwardly and therewith link 28! of toggle linkage 285, 288 also is moved upwardly, whereby the length of the linkage is decreased. Consequently, a pull is exerted on regulator rod 296 which tends to withdraw rod 296 from regulator casing 291. The amount of adjustment effected hereby depends on the control movements of bell-crank 282, 284, influenced by curve disc 280, besides being dependent on the control movements of the centrifugal governor. According to the invention the various cooperating gear members are so dimensioned and arranged that the feed movement of regulator rod 296 is compensated again by bell-crank lever 282, 284 by shortening toggle lever system 285, 286 acted upon by the centrifugal governor.

In the construction shown in Fig. 5 the engine block of the internal combustion engine is designated with 380. Pipe 302 is connected to the rear part 30| of the casing. The other end of pipe 302 ends in Venturi tube 303, the open mouth of which faces the relative air current which flows into the mouth as indicated by the arrow. Tappings 304 and 305 are provided on Venturi tube 383 in the same manner as tappings 2| and 22 described in connection with the construction shown in Fig. 1. Pipes connected to tappings 384, 385 lead to regulator 306 which is constructed in a well-known manner and measures the weight of the quantity of combustion air drawn in. Rod 38! projects from regulator 306 which is by means of a link, connected to a further rod 388 which in turn is by a link connected to rod 389. Rod 309 is connected by a link to rod 3|0 which preferably also acts by way of a link upon rod 3 formed as a regulating rod of fuel pump 3|2 and movably arranged in the casing of pump 3|2.

Regulator 3|3 controlling the number of revolutions is mounted in adjustable propeller 3|4 journalled upon shaft 3|5 and driven by the internal combustion engine 300. Regulator 3|3 is according to the invention so constructed as to change the position of the blades of the propeller in such a manner that the driving engine always rotates with a constant number of revolutions.

Figs. 68 illustrate by way of example the coupling of the pilot lever to the selecting lever for the adjustment of the various ranges of numbers of revolutions of the propeller. 3|3 is the handle of pilot lever 3|!. The two levers 3!! and 32| bear by means of hubs 3l8 and 320, respectively, against a common pivot 3l8. Recess 322 facing lever 3!! is provided in lever 32!. Projection 323 of lever 3!! may engage with recess 322 to couple the two levers 3|!, 32|.

The so-called pilot lever as well as the selecting lever for the number of revolutions of the ad- Justable propeller are movable in common slide 324 provided wtih slot 325.

As may be seen in Figs. 6 and 8, pilot lever 3l8, 3!! may be moved in slot 325 of slide 324 from point a over b to c, then to d and finally to e. In the positions a and e lever bears against stops which are formed by slot 325 of slide 324.

a designates the idle running position, b and c designate the cruising positions corresponding to 80% of the nominal output, while d is the position for the nominal output and e is the position for take off output.

0n shifting pilot lever 3 I 8, 3 I from the position 0 to the position if and e selecting lever 32! is entrained by nose 323 which engages with recess 322. Hereby selecting lever 32! is moved from the position 0 (see also Fig. 5) which corresponds to the low number of revolutions of the propeller into the positions d and e which correspond to the high number of revolutions.

If levers 3|6, 3!! and 32| are not coupled to each other, selecting lever 32| always is maintained in the position 0 by means of spring 328, whereas pilot lever 3l8, 3|! may be maintained in any desired position.

Another modification of the present device has the advantage that it may be used for controlling the quantity of the fuel and also for controllin 40 auxiliary devices of the internal combustion engine, as for instance the ignition device, the cooling apparatus, the adjustable propeller and so on. The device is constructed to also operate under the following operating conditions.

If for instance an aircraft is flying in a height substantially above the so-called full pressure height, the engine supplies a certain portion of its full eflciency only due to the reduction of the charging pressure. Supposing for instance, the motor only supplies of its full power during the time the pilot lever occupies the 100% position very unfavorable conditions result in connection with the known devices. For instance, the coolin flaps are completely opened, whereas the engine only supplies half of its full power so that the englue is strongly cooled down and the speed of the aircraft is unnecessarily reduced. Also the time of ignition can not be correctly adjusted as with the 108% position of the pilot lever the times of ignition favorable for full load are set, whereas due to the great height of the aircraft about 50% of the engine efliciency only may be obtained. The same is true for instance for the adjustment of the pitch of the propeller and the setting of other devices.

To obviate these defects, the regulating device according to the invention is so constructed that a time of ignition, different from that required for a smaller quantity of air fed, for instance corresponding to the cruising efficiency is automatically set, when larger quantities of air corresponding to a great engine emciency are dealt with in aunit of time.

Also the blades of an adjustable propeller are set and the position of the louvers allowing dislaw. Bymeans of spring 433 roller 443 is always charge of the cooling air is regulated in such a sense that above a definite height of flight in which the engine cannot operate with highest efflciency because the amount of air drawn in in a unit of time is too small the cooling flaps cannot longer be completely opened.

In the modification shown in Fig. 9 by way of example only one cylinder 48! is represented of the internal combustion engine used. Piston 402 moves up and down in cylinder 48! and is connected by rod 483 to crank 404 of crankshaft 465. Outlet valve 486 of cylinder 48! is connected to pipe 401 leading to the exhaust, and inlet valve 488 is provided in cylinder 46!. Gear wheel 489 is mounted upon shaft 485 and engages with gear wheel 458 mounted on shaft 4! Shaft 4!! carries rotor 4!2 of a centrifugal blower serving as charger, the fixed casing 4! 3 of which is connected by pipe 4!4 to inlet valve 468 and supplies valve 448 with combustion air under pressure.

Nozzle 4! 5 for injecting fuel extends into pipe 4l4. Nozzle M5 is connected to fuel pump 4!6 which is formed for example as a geared pump 4H5 the construction of which is known and, therefore, this pump need not be described in detail. The quantity of fuel fed by fuel pump M6 is controlled also in a well-known manner by lever 4!1 acting upon a control valve of the pump which also is well-known and, therefore, not .shown in the drawings.

Air is supplied to centrifugal blower 4i 2, 4! 3 by Venturi tube 4ft open to the relative air current. The discharge end 4.!9 of Venturi throat M8 is narrow and flares like a diffuser towards the charger up to th width of inlet socket 428. At the smallest portion as well as at the largest portion of Venturi tube 4!8 tappings 42! and 422 respectively, are provided. Tapping 422 is connected by pipe 428 to the interior space 424 of chamber 425. Diaphragm box 426, formed by a corrugated tube is arranged in the interior space 424 closed against the outer atmosphere. The interior of bellows 426 is connected by pip 421 to tapp ng 42!. The pressure differenc occurring at tappings 42! and 422 of Venturi tube 4l8 due to'the ilow of air effects an expansion or contraction of diaphragm box 426. Rod 428 is rigidly connected tobellows 426 and is actuated by its expansion and contraction movements. 43!! are mounted in rod 428. Pistons 429, 430 are displaceably arranged in sleeve 43! which in turn is displaceably arranged in cylinder 432. An inlet pipe 433' and two outlet pipes 434, 435 for admitting and discharging pressure oil are provided in cylinder 432. Moreover, cylinder 432 is connected to chambers 438, 439 arranged above and below piston 440, respectively, by means of channels 436, 431. Pistons 429 and 438 effect in a well-known manner admission and discharge of pressure 011 into and out of chambers 438 and 439, respectively, whereby piston 44!) is moved upwardly or downwardly. The admission and discharge of the pressure oil, besides dependin on the position of pistons 429, 438, depends on the position of sleeve 43! and the openings provided in sleeve 43!. Piston rod 44! carrying cam 442 i attached to piston 448. Cam 44!! is formed in the manner of a logarithm curve. Roller 443 bears against cam 44!] and is carried by th one arm 444 of a bell-crank pivotally mounted on bolt 445. The other arm 446 of the bell-crank is fork-shaped and engages pin 441, provided on rod 448 rigidly connected to sleeve 43!. In this manner piston 448 controls sleeve 43! according to a logarithm Two pstons 429, I

pressed against curve 442.

The lower end of rod 44! carries pin 449 which engages fork 450 of balance beam 45! and acts upon the latter. Piston rod 453 controlled by piston 454 acts upon the other arm of balance beam 45! which also is formed with a fork-shaped end 452. Piston rod 453 carries curve 455 which also is formed in the manner of a logarithm curve which, however, extends in a reverse direction with regard to curve 442. Roller 456 bears against curve 455 and is carried by lever arm 451 of a bell-crank, pivotally mounted upon bolt 458. The other fork-shaped arm 459 of the bellcrank engages pin 468 which is provided on rod 462 rigidly connected to sleeve 46!. Against the action of spring 463 sleeve 46! may be displaced in a cylinder 464 provided with an inlet 465 and two outlets 466 and 461 for pressure oil. Channels 468, 469 are provided on the other side of sleeve 46!. According to the position of sleeve 46! and pistons 41!], 41! displaceably arranged in said sleeve, channels 468, 469 effect the admission and discharge of pressure oil into and out of chambers 412, 413 above and below piston 454. Pistons 418, 41! are fixed to piston rod 414 attached to diaphragm box 415, 'formed by a corrugated tube. Pistons 418, 41! are controlled by the expansion and contraction movements of diaphragm box 415. Diaphragm box 415 is closed against the outer atmosphere and contains a definite weight of air, whereas atmospheric pressure prevails in space 416 of chamber 411 which surrounds diaphragm box 415 so that bellows 415 expands and contracts in dependence on the state of air at a given time.

Rod 41.9 is linked to point 418 in the middle of balance beam 45!. As piston 448 due to the control of sleeve 43! transfers upon balance beam 45! the logarithm value of the pressure difference existing at the two measuring points 42!, 422, while piston 444 transfers upon balance beam 45! the negative logarithm value of the state of air, a displacement of rod 419 results, corresponding to half the difference of the logarithm value of the pressure difference and the logarithm value of the state of air. Rod 419 carries a further push curve 480 which introduces into the calculation the constant and the root value of the formula G: av

referred to hereinbefore. The one arm 482 of a bell-crank pivoted on bolt 483 bears by means of roller 48! against curve 488, while the other arm 484 of the bell-crank acts upon lever 4!'!. In this manner the fuel supply is effected in dependence on the actually consumed weight of air at a given time. Two pistons 485, 486 are mounted on rod 419. In correspondence to the position of rod 419, pistons 485, 486 are displaced in sleeve 481 shiftably arranged in cylinder 488. Pressure oil is admitted to and discharged from cylinder 488 by way of inlet pipe 489 and discharge pipes 498, 49!. Sleeve 481 is provided with openings which substantially correspond to the openings of the cylinder. Cylinder 488 is connected by means of two channels 492, 493 to chambers 494, 495 arranged above and below piston 496, respectively, so that in a manner known per se the position of pistons 485, 486 as well as the position of sleeve 49! control the position of piston 496. Piston rod 491 carrying curve 98 is fixed to piston 496. Roller 499 mounted on arm 500 of a bell-crank pivoted at M bears against curve 98. The other arm 502 of the bellcrank is fork-shaped and engages pin 50": of piston rod 504 which bears against sleeve 1 and displaces the latter against the action of spring 505. Rod 491 acts upon a lever, not shown in the drawings, which in a manner known per se effects adjustment of the ignition device, ad-

justment of the cooling flaps or setting of the blades of a variable propeller. One and the same piston 496 may effect the adjustment of all adjustable devices, but separate devices also may be provided for adjusting each individual device.

By the above mentioned device not only the fuel supply but also the regulation of all devices, the optimum position of which changes in accordance with the engine efficiency, are directly controlled in dependence on the quantity of the fuel mixture consumed by the engine.

Although preferred embodiments of the regulating device have been disclosed in accordance with the present invention, it is to be understood that variations and modifications therein may be made coming within the broader spirit and scope thereof as defined in the following claims.

We claim:

1. In combination with an internal combustion engine, a controllable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, an ignition device for said engine, a fuel pump, a cooling apparatus for said engine, a charger comprising an air intake, an auxiliary motor for said charger, means for continuously measuring the weight of the air passing through said air intake, means to automatically control in accordance with the measured weight of the air said fuel pump, said setting device for setting the propeller pitch, said auxiliary charger motor, said cooling apparatus, and said ignition device, and means for operatively connecting said control means with each of said devices controlled thereby.

2. In combination with an internal combustion engine, a variable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, an ignition device for said engine, a fuel pump, a cooling apparatus for said engine, a charger comprising an air intake, an auxiliary motor for said charger, means for continuously measuring the weight of the air passing through said air intake, control means operating in accordance with the measured weight of the air, a regulating device connected with said control means and controlling in turn simultaneously said fuel pump, said setting device for adjusting the pitch of said propeller, said auxiliary charger motor, said cooling apparatus, and

said ignition device, and means to operatively connect said regulating device with each of the devices to be controlled.

3. In combination with an internal combustion engine, a fuel pump. a charger having an air intake, said air intake comprising a Venturi tube,

trollable pitch propeller to a constant number of revolutions, a linkage connecting said support with said fuel pump, said governor further controlling said linkage, whereby the weight of the fuel delivered by said pump depends upon the weight of the air as well as on the number of revolutions of said engine.

4. In combination with an internal combustion engine, a fuel pump, a charger having an air intake. said air intake comprising a Venturi tube,

- a balance beam comprising two arms, means to a balance beam comprising two arms, means to actuate one of said arms by the logarithmic value of the pressure diflerence of the air passing through the widest part and through the narrowest part of said Venturi tube, means to actuate the other of said arms by the negative logarithmic value of the variations in the specific volume of the air, a support connected with the fulcrum of said two arms, a controllable pitch propeller coupled to said engine, a centrifugal governor controlled by the number of revolutions of said engine and comprising a mechanism for automatically setting said controllable pitch propeller to a pulrality of predetermined constant number of revolutions, a control means connecting said support with said fuel pump, the mechanism of said governor further controlling said control means, whereby on setting a range of higher number of revolutions said control means'simultaneously and automatically controls said fuel pump to effect an enrichment of the fuel air mixture.

5. In combination with an internal combustion engine,-a variable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, a charger having an air intake comprising a Venturi tube, a fuel pump, a balance beam comprising two arms, means to influence one of said arms by the pressure difference ofthe air passing through said Venturi tube, a bellows controlling the other of said arms, said bellows being influenced by the variations of the specific volume of the air, means to convert said two influences to the weight value of the air being proportional to the square root of said air pressure difference divided by said specific air volume, said means actuating a further control means in accordance with said air weight value, said further control means controlling said fuel pump, and said setting device for adjusting the pitch of said propeller, and means to operatively connect said further control means with each of said devices controlled thereby.

6. In combination with an internal combustion engine, a variable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, a charger having an air intake, said air intake comprising a Venturi tube, a fuel pump, a balance beam comprising two arms, a first linkage influenced by the pressure difference of the air passing through said Venturi tube, said first linkage controlling one of said arms, a second linkage, a bellows connected with said second linkage and controlling the other of said arms, said bellows being influenced by the variations of the specific volume of the air, said linkages including actuating cams, shaped according to a logarithm law, for converting the algebraic quotient of the square root of said air pressure difference divided by said specific volume to the difference between the logarithm of said pressure difference and the logarithm of said specific volume a rod connected with the fulcrum of said balance beam, said rod comprising a further cam formed in accordance with the number value for retransforming the logarithmically efiected movements in movements according to the law oi the air weight being proportional to the square root of said air pressure difierencedivided by said specific air volume, said rod controlling said fuel pump, and said setting device for adjusting the pitch of said propeller, said rod being operatively connected with each of said devices controlled thereby. I

7. In combination with an internal combustion engine, a controllable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, a charger comprising an air intake, said air intake including a ,Venturi tube, an auxiliary motor for said charger, a fuel pump, a cooling apparatus for said engine, an ignition device for said engine, a balance beam comprising two arms, means to influence one of said arms by the pressure difference of the air passing through said Venturi tube, a bellows closed and filled with air influencing the other of said arms, said bellows being actuated in accordance with the specific volume of the air, means to convert said two influences to the weight of the air being proportional to the square root, of said air pressure difierence divided by said specific air volume, said last means actuating a further control means in accordance with said air weight, said control means controlling "said fuel pump, said setting device for adjusting the pitch of said propeller, the auxiliary motor for said charger, said cooling apparatus, and said ignition device, and means to operatively connect said control means with each of said devices controlled thereby.

, 8. In combination with an internal combustion engine, a controllable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, a charger comprising an air intake, said air intake including a Venturi tube, an auxiliary motor for said charger, a fuel pump, a cooling apparatus for said engine, an ignition device for said engine, a balance beam comprising two arms, a first linkage influenced by the pressure difference of the air passing through said Venturi tube and controlling one of said arms, a second linkage, a bellows closed and filled with air and connected with said second linkage, said second linkage controlling the other of said arms, said bellows being actuated in accordance with the specific volume of the air, said linkage including actuating cams, shaped according to a logarithm law, for converting the algebraic quotient of the square root of said air pressure difference divided by said specific air volume to the said charger, a fuel pump, a cooling apparatus for said engine, an ignition device for said engine, a

difference between the logarithm of said pressure difierence and the logarithm of said specific vol ume, a rod connected with the fulcrum of said balance beam, said rod having further cams formed in accordance with the numbervalue for retransforming the logarithmically effected movements in movements according to the law of the air weight being proportional to the square root of said air pressure difierence divided by said specific air volume, said rod controlling said fuel pump, said setting device for adjusting the pitch of said propeller, the auxiliary motor for said charger, said cooling apparatus, and said ignition device, and means to operatively connect said rod with each of said devices controlled thereby.

9. In combination with an internal combustion engine, a variable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, a charger having an air intake comprising a Venturi tube, an auxiliary motor for balance beam comprising two arms, means to actuate oneof said arms by the logarithmic value of the pressure difference of the air passing through the widest part and through the narrowest part of said Venturi tube, means to actuate the other of said arms by the negative logarithmic value of the variations in the specific volume of the air, a rod connected with the fulcrum'of said balance beam and actuated thereby in accordance with half of the difference between the logarithmic value of said pressure difference and the logarithmic value of said specific air volume, said rod being connected with said fuel pump for controlling said pump, whereby the weight of the fuel is controlled in dependence upon the weight .of the air, said rod being further connected with and controlling said ignition device, said cooling apparatus, said setting device for adjusting the pitch of said propeller, and said auxiliary charger motor.

10. In combination with an internal combustion engine, a variable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, a charger having an air intake comprising a Venturi tube, an auxiliary motor for said charger, a fuel pump, a cooling apparatus for said engine, an ignition device for said engine, a balance beam comprising two arms, means to actuate one of said arms by the logarithmic value of the pressure difierence of the air passing through the widest portion and through the narrowest portion of said Venturi tube, means to actuate the other of said arms by the negative logarithmic value of the variations in the specific volume of the air, a rod connected with the fulcrum of said two arms and actuated thereby in accordance with half of the difference between the logarithmic value of said pressure diiference and the logarithmic value of said specific air volume, said rod controlling a pressure operated piston, said piston bein operatively connected with and controlling in turn simultaneously said fuel pump, said setting device for adjusting the pitch of said propeller, said auxiliary charger motor, said cooling apparatus, and said ignition device, whereby the weight of the fuel is controlled in dependence upon the weight of the air.

11. In combination with an internal combustion engine, a variable pitch propeller driven by said engine, a setting device for adjusting the pitch of said propeller, a charger having an air intake comprising a Venturi tube, an auxiliary motor for driving said charger, a fuel pump, a cooling apparatus for said engine, an ignition device for said engine, a balance beam comprising two arms, a first means including a cam connected with and actuating one of said arms, said first means being controlled by the logarithmic value of the pressure difierence of the air passing through the widest part and through the narrowest part of said air intake, a second means including a cam connected with and actuating the other of said arms, said second means being controlled by the negative logarithmic value of the variations in the specific volume of the air and being further controlled by the negative expansion value of said Venturi tube in different air densities, said last mentioned cam being shaped in the form of a curve having superposed the negative logarithmic value of the variations in the specific volume of the air and the negative expansion value of said Venturi tube in diiferent air densities, a rod. connected with the fulcrum of said two arms and actuated in accordance with half the difierence of the logarithmic value of said pressure difference and logarithmic valu of said specific volume of the air and by said negative expansion value, said rod controlling said fuel pump, whereby the weight of the fuel is controlled in dependence upon the weight of the air, said rod being further operatlvely connected with and controlling simultaneously said setting device for adjusting the pitch 0! said propeller, said auxiliary charger motor, said cooling apparatus, an said ignition device.

FRITZ GOSSLAU. JOHANNES SCHMIDT. WERNER ZARNACK. 

